There is a Trojan out there that covers as a Microsoft utility.
The Ransom-AN Trojan says a user’s machine is running an unlicensed copy of Windows and threatens to cripple the victim’s computer unless he pays a certain amount to obtain an unlock code. The victim can then purchase that key via credit card at a scam website.
The malware attempts to scare users with claims that a criminal prosecution will launch unless they get a payment within 48 hours. In addition, the Trojan said all data and applications on targeted systems will be “permanently lost.”
The malware, which targets German-speaking users, is going out via spam and P2P downloads. Panda Software, the Spanish net security firm which detected the threat, warned the Trojan is difficult to remove manually.
“These types of Trojans are very dangerous because once they infect the computer it is extremely difficult to remove them manually, forcing users to pay the ransom or reformat their devices,” said Luis Corrons, technical director of PandaLabs. “In addition, because Ransom.AN appears to come from Microsoft and threatens actions from authorities, many users believe what the Trojan says and make the payment out of fear.”
Previous ransomware strains have encrypted files in a bid to force users into paying for getting infected. The tactics used by Ransom-AN Trojan are a more aggressive extension of the basic scam, using threats of prosecution and outwardly convincing screenshots supposedly from Microsoft to peddle the ruse.